Hi Kim, Welcome!

These three bikes are very popular and, I think, very similar. You'll see many posts where people are comparing these same three. They're all in the same category, so test ride them all, and see which one fits the best (remember, fit can be adjusted), rides/handles the way you like, or just makes you happy! Each one comes with different component groups, so try to compare similar models.

Have fun, and be careful. I ended up with both a Synapse and a Dolce in my stable